1. Field of the Invention
The present invention relates to small form-factor pluggable (SFP) modules, and particularly to SFP modules having release devices which are used to withdraw the SFP modules from SFP cages.
2. Description of Related Art
Nowadays SFP transceivers are being more and more widely used for bi-directional transmission of data between an electrical interface and an optical data link. An SFP transceiver receives electrically encoded data signals, converts them into optical signals, and transmits the optical signals over the optical data link. The SFP transceiver also receives optically encoded data signals, converts them into electrical signals, and transmits the electrical signals onto the electrical interface.
The SFP transceiver is generally encased in an SFP cage. The cage has standardized features that comply with the SFP transceiver multi-source agreement (MSA). The cage conventionally comprises spring means located in a rear portion thereof. When the SFP transceiver is withdrawn from the cage, an ejecting block of the SFP transceiver forces a latch of the SFP transceiver out from a retaining hole defined in a retaining tab of the cage. The latch is released from the retaining tab. The SFP module is then ejected from the cage by the spring means. The MSA also specifies an exemplary release device for an SFP module. The SFP module defines a guide rail at a bottom of a front portion thereof. An ejecting block slidably engages in the guide rail at the bottom of the SFP module. In order to withdraw the SFP module from the cage, the ejecting block is manually pushed inwardly under the SFP module. However, it is inconvenient to manually push the ejecting block at that location. This is particularly so in modem systems having high port densities in and around the cage that restrict access to the ejecting block.
Accordingly, an object of the present invention is to provide an SFP module having a release device which is readily operated in front of the SFP module.
In order to achieve the object set above, an SFP module in accordance with a preferred embodiment of the present invention comprises a housing and an ejector. An ejector seat is formed at a front section of a lower portion of the housing, for receiving the ejector. Two retaining blocks are formed on the ejector seat, for preventing the ejector from falling out of the ejector seat. A triangular latch is integrally formed on a bottom surface of the lower portion of the housing, behind the ejector seat. The ejector includes a push bar, a main body, and a tongue board. Two slanted ejecting protrusions are formed at respective opposite sides of a rear end of the tongue board, corresponding to a bent portion of a spring tab of an SFP cage retaining the SFP module therein. The spring tab defines a retaining hole for retaining the latch of the housing. The push bar is exposed forward of a front end of the housing. To withdraw the SFP module from the cage, the push bar is pushed until the ejecting protrusions of the ejector have released the spring tab from the latch of the housing. The SFP module is then ejected from the cage by conventional spring means located in a rear portion of the cage.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: